Larviculture of Yellow Mandi Pimelodus maculatus Lacépède, 1803 (Siluriformes: Pimelodidae) at Different Stocking Densities during the First Days of Life

Este trabalho foi realizado na Estação de Piscicultura de São Carlos (EPISCar), São Carlos, SC. O efeito da densidade de estocagem de Pimelodus maculatus na larvicultura foi avaliado em pós-larvas alimentadas diariamente com zooplâncton selvagem na proporção de 300 organismos/pós-larva/dia e submetidas aos seguintes tratamentos: T1 - 5 pós-larvas/litro; T2 - 15 pós-larvas/litro; T3 - 30 pós-larvas/litro. No terceiro e quinto dias de experimento, foi avaliada a taxa de sobrevivência. Decorridos três dias de experimento, não foi observada influência da densidade na sobrevivência, embora, no quinto dia de experimento, houvesse maior sobrevivência na menor densidade testada, com valores médios de sobrevivência final de T1 (35,6%), T2 (28,9%) e T3 (20,6%). Os maiores valores de peso foram encontrados no tratamento de menor densidade, sendo os valores de comprimento semelhantes entre os tratamentos. O tratamento contendo 30 pós-larvas/L apresentou as menores taxas de sobrevivência e a maior produtividade final.The effect of stocking density on the larviculture of Pimelodus maculatus post-larvae was evaluated. The experiment was conducted at the Sao Carlos hatchery (EPISCar), SC. Post-larvae were daily fed zooplankton at the rate of 300 organisms/post-larvae/day at the following densities: T1. 5 post-larvae/L; T2. 15 post-larvae/L; and T3. 30 post-larvae/L. Survival rates were evaluated on the third and fifth day of the experiment. After three days, density did not affect survival rates; however, on the fifth day survival rate was higher for the lowest density. Average survival rates at the end of the experiment were 35.6, 28.9 and 20.6% for T1, T2 and T3, respectively. Post-larvae average weight was also higher at the lowest density, but average length did not differ significantly among treatments. At density of 30 post-larvae/L, post-larvae survival rate was the lowest, but final productivity was the highest